The present invention relates to thermal interface materials for cooling systems used on multiple integrated chip devices assembled on a common printed circuit board, and methods for forming the same.
Electronic packaging designs continue to trend toward increased density. A by-product of this trend is the application of multiple integrated chip devices assembled to a common printed circuit board. Due to the increasing package density, more and more devices require active thermal cooling. Multiple devices with different mechanical sensitivities, heights, and thermal power dissipation characteristics mounted on the same printed circuit board may need cooling simultaneously.
If a single cooling device, such as a cooling plate, is used to cool multiple devices, thick gaps of variable size may exist between the devices and the cooling plate. Thermal interface materials may be used to couple the devices with the cooling plate. During assembly, thermal interface materials thick enough to fill the gaps, such as thermal gap pads, may exert mechanical stress on the devices capable of creating short-term and/or long-term damage. Less rigid thermal interface materials, such as thermal gels, may dissociate from the device during expansion and contraction associated with the device's thermal and/or power-on/off cycles.